Just checked and all my cris labels and lozenges show our eriba 17 digit vin ref starting WHYTR..........

All UK manufactured WWB's are delivered with CRIS decals already fitted on the windows. At least owners then don't have to fiddle about fitting than. To my eye they were invisible, just like the manufacturer's bits of writing on the plastic, though if you've fitted them yourself they assume more visibility in your mind. I suspect they'd only deter a thief if they covered half a window and flashed red and yellow, as they are, they're just part of the scenery.